The crown prince is regarded as the lonely reformer in Bahrain’s ruling family, worthy of consulting but not in a visible way that might confuse people that the US condones the crackdown. His great-uncle, Prime Minister Khalifa bin Salman, is the conservative – and brutal – one, defending the country’s minority Sunni elite against the pro-democracy rabble with an iron fist. He might also have the power to boot out the US Naval base.

“Drop by” meetings are often used by presidents to send or receive messages in situations that need delicate diplomacy. The Dalai Lama, for example, gets such treatment, so as not to offend China by holding an official, cameras-clicking meeting.